Combined typewriting and computing



Aug. 8, 1939.

H. L. PITMAN COMBINED TYPEWRITING AND COMPUTING MACHINE Original Filed March 25, 1932 5 Sheets-Sheet 1 R. m n m m V, 0 m? n A g W g @Q Q Q Q Q Q SQ Q l r; s mdt Q .s xv Q .Q Q Q Q QR w Aug. 8, 1939. H. PITMAN COMBINED TYPEWRITING AND COMPUTING IACHINE Original Filed March 25, 1932 5 Sheets-Sheet 2 IN V EN TOR.

ATTORNW Aug. 8, 1939- H. L. PITMAN COMBINED TYPEWRITING AND COMPUTING MACHINE Original Filed March 25, 1932 5 Sheets-Sheet 3 ATTORNI/EW Aug. 8, 1939. H. L. PITMAN COMBINED TYPEWRITING AND COMPUTING IACHINE 5 Sheets-Sheet 4 Original Filed March 25, 1932 dEE TTORNEY.

Aug. 8, 1939. H L pn- 2,168,538

COMBINED TYPEWRITING AND COMPUTING MACHINE Original Filed March 25, 1932 5 Sheets-Sheet 5 FIGJZ.

n n n n n n n F INVENTOR.

A TTORNEY,

, Patented Aug.

UNITED STATES PATENT OFFICE comnnvnn mnwarrmo MACHINE Ag'D COMPUTING Henry L. Pitman, Hartford, Conn., assignor to Underwood Elliott Fisher Company, New York,

N. Y., a corporation of Delaware Original application March 25, 1932, Serial No. 601,173. Divided and this application March 12, 1937, Serial No. 130,535

2 Claims.

10 plifying said machine, and for simplifying the tens-carrying mechanism and overthrow-preventing mechanism of said machine.

The Underwood-Hanson machine is described in the patent to O. Minton No. 1,280,065 dated 13 September 24, 1918, which also discloses the Underwood subtraction mechanism, whereby subtraction is effected by adding the usual complement of the subtrahend. I

Tens-carrying mechanism of the Underwoodm Hanson machine is described in Patent No. 1,278,812 to H. Hanson, dated September 10, 1918.

According to the present invention, the subtraction-mechanism is much simplified in coma parison with the Underwood subtraction mechanism described in the aforementioned patent to Minton No. 1,280,065. State-determining means are provided whereby the dial-wheels are caused to rotate in one direction for addition or to roo tate reversely for subtraction. The subtraction is therefore direct, as distinguished from subtraction effected by adding the complement of the subtrahend.

In the present invention, the register-bars hava ing the computing wheel driving racks and the index-pins are retained. For addition the computing wheels are driven directly by said driving racks, whereas for subtraction the computing wheels are driven by intermediate rotation-reo versing pinions or racks which may be permanently in mesh with the driving racks. The computing wheels are normally disengaged from both the driving racks and the intermediate pinions, and by the state-determining means are brought 5 into mesh, either with the driving racks on the register-bars or with the intermediate pinions, during an initial portion of the advance movement of the general operator, depending on the setting of the state-determining means. Said 50 state-determining means may be normally set or conditioned for addition so that normally the computing wheels will be directly driven by the driving racks on the register-bars. For subtraction said state-determining means may be con- 55 ditioned as by the operation of a subtraction-key to bring the computing wheels into engagement with the intermediate pinions.

The computing wheels remain in mesh throughout the rest of the advance movement of the general-operator cross-bar.

Driving means for said general-operator cross-bar may be so arranged that at the end of said advance movement said general-operator cross-bar stands stationary for an interval of time to insure completion of the tens-carrying operation, as will hereinafter be made clear, the return movement of the general-operator cross-bar being commenced at the end of said interval. In the initial portion of said return movement, the computing wheels are caused to be disengaged before the general-operator cross-bar picks up the advanced register-bars to restore them to their normal positions.

thus disengaging the computing wheels, before the return of the register-bars, the necessity for providing one-way connections of the computing wheels to the register-bars is avoided, with consequent simplification of the mechanism.

The carrying of tens from one computing wheel to another computing wheel of the next higher denomination involves the release of a springpressed normally latched register-bar stop general-operator cross-bar.

When said registerbar stop is released from its latch, and is, in consequence, caused to be withdrawn by its spring, the register-bar is permitted to advance an extra unit space to thereby carry over a tens value, said stop being still effective, however, to prevent overthrow of the register-bar, since it is only withdrawn enough to permit said extra advance.

If a register-bar stop be released and withdrawn before the general operator reaches the end of its advance movement, the register-bar which said stop controls is, according to an important feature of the invention, advanced positively for carrying, by the movement of the general-operator cross-bar as"it completes its advance stroke.

To this end, the general-operator cross-bar does not engage the indexpins directly for advancing the register-bars, but there are interposed ahead of said cross-bar for engaging the index-pins, the ends of a series of levers of the first order pivoted on a fulcrum-rod ried by the general-operator cross-bar.

car- The other and normally free ends of said levers are, in the direction of cross-bar movement, opposite the free ends of a series of similar levers of the first order pivoted on a fixed fulcrum-rod, the other ends of said latter levers being connected to the aforesaid register-bar stops. The levers connected to said stops are capable of two positions, depending on whether or not the stop is withdrawn for carrying. If a stop is not withdrawn for carrying, the free end of the lever connected thereto just meets the free en of the opposite lever on the fully-advanced ne'raloperator cross-bar. The two levers thus meeting form a pincer-like arrangement wherein the index-pin is held between the register-bar stop and the opposite end of the lever on said cross-bar, said cross-bar backing up said opposite lever end. Thus the advanced position of the register-bar is secured against overthrow and also against rebound. Should a register-bar stop be withdrawn before the general-operator cross-bar reaches the end of its advance movement, the free end of the lever connected to said register-bar stop will be moved toward the free end of the opposite lever on the approaching cross-bar and thus constitutes an interponent which will engage and arrest said free end of the cross-bar lever Just before the cross-bar completes its advance movement.

It will be understood now that as said crossbar advance movement is completed, the lever on the cross-bar will be rocked because of the arrest of its free end, thereby causing an extra tens-carrying advance of the register-bar, the extra advance being positive due to the positively driven cross-bar. proportioned that when a sufllcient extent of carrying advance is reached, the index-pin is again held between the register-bar stop and the opposite end of the lever on the cross-bar to prevent overthrow or rebound of the registerbar. The free ends of the two series of levers may be proportioned and arranged so that the levers connected to the register-bar stops may look the levers on the cross-bar against reverse movement at the end of a carrying movement of said cross-bar levers. Such proportioning and arrangement of said free ends are also effective to stabilize the levers connected to the registerbar stops as' their free interponent ends co-operate to rock the cross-bar levers, inasmuch as the lines of reaction, which the free ends of said stop-levers afford to rock the cross-bar levers and lock the same against reverse rotation, may in either case pass through the fulcrum center of said stop-levers.

If, as may happen in some computations, a register-bar stop he released and withdrawn for carrying a tens value after the general-operator cross-bar has completed its advance movement, the carrying advance of the register-bar controlled by said stop may be effected by power derived from suitable springs connected either to the register-bar stop or its lever. In this case it will be understood that the free ends of the stop-lever and the opposite cross-bar lever just meet as the cross-bar completes its advance and that a subsequent release and withdrawal of the stop will cause the lever connected therewith to be rocked by the power of the aforesaid spring, with a consequent rocking of the lever on the cross-bar and a consequent carrying advance of the register-bar whose set index-pin is held between the register-bar stop and cross-bar lever as aforesaid. v

It will be seen now that the OHM-D94 l y The levers may be so nected at one of their ends to their respective levers, said ends also forming the stop or abutment between which and the cross-bar lever or finger, the index-pin is held at the end of the register-bar movement. Said stop-bars, viewed sidewise of the register-bars, may extend substantially parallel to the latter and may be latched at their other ends over a latching bar. Each computing wheel may have the usual carrying tooth. Said tooth, in the preferred form of the invention, does not, for carrying as aforesaid, release the corresponding registerbar stop by direct engagement, but instead, for

convenience of arrangement of the parts, re-

leases said stop through an intermediate carrying lever, one end of which may be engaged by said carrying tooth, and the other end of which may engage the stop to displace the same from the latching bari The tooth-actuated carrying levers maybe mounted in the aforesaid frame, in which the computing wheels are mounted, and may be so arranged that the ends which engage the stops may properly engage said ends irrespective of the shifting of said frame either toward the register-bar racks or toward the intermediate racks.

This application is a division of my co-pending application Serial No. 601,173, filed March 25, 1932, (now Patent No. 2,078,274, dated April 27, 1937) which is a continuation in part of and co-pendent with my application No. 324,353, filed December 7, 1928 (now Patent No. 1,927,951, dated September 26, 1933).

Other features and advantages will hereinafterappear.

In the accompanying drawings- Figure 1 is a cross-section through the combined typewriting and computing machine, showing, in side elevation, details of the novel carrying mechanism.

Figure 2 is a side elevation, showing details of one form of power-drive for the computing mechanism.

Figure 3 is a detail view, showing the construction of means whereby a universal bar for restoring the carrying stops is operated.

Figure 4 is a top plan view, looking down on the computing mechanism, to show the arrangement of four registers, and the operating parts for said registers.

Figure 5 is a skeleton view, showing, in perspective, the arrangement of said four registers,

and the arrangement of a register-bar, relatively to the novel carrying means, and also bringing out other details of construction.

Figure 6 is a skeleton view, showing, in perspective, the fixed plates within which a registerwheel frame is shifted, and also showing, in detail, means for ensuring relatching of carrying stops.

E8 7 5 8 view, showing, in perspective,

, fixed plates.

Figure 9 is a side view, illustrating means and the operation thereof for shifting the aforesaid latching bar.

Figures and 11 are enlarged side views, showing details of the novel carrying mechanism, Figure 10 showing said mechanism in normal position, and Figure 11 showing said mechanism operated to effect the carrying" of a number.

Figures 12, 13 and 14 are each a side view of a register-bar and the train of carrying parts extending from one computing wheel to the regis'ter-bar of next higher denomination. Figure 12 shows a computing wheel directly engaged with the register-bar for addition, and also shows a register-bar in advanced position without having carried. Figure 13 is similar to Figure 12, but shows the register-bar advanced for carrying. Figure 14 shows a computing wheel not directly connected to the register-bar rack, but connected thereto by the intermediate pinion to reverse the rotation of said wheel for subtraction, Figure 14 also showing the register-bar advanced for carrying, and, compared with .Figure 13, showing that the carrying advance of a registerbar is the same for subtraction as it is for addition.

Figures and .6 are partial plan views of means forming the power-drive shown in Figure 2.

As seen in Figure 1, the novel computing mechanism co-operates with a typewriter in which numeral-keys l0 mounted on key-levers ll may, through other members of the usual type-action, cause types l2 to print against a platen l3. Said platen I3 is in a carriage l4 traveling on rails i5 and I6 of the typewriter-framework II. By operation of the type-keys said carriage is propelled in letter-feeding steps determined by an escapement-mechanism l8 under control of said keys and spring-motor IS.

The computing mechanism may include one or more sets of computing wheels 20, Figure 4, in dicating four sets of computing wheels. For each computing wheel there is a register-bar 2| carrying a series of downwardly-settable index-pins 22, for the digits from 0 to "9. As disclosed in my co-pending Patent No. 1,869,582, dated August 2, 1932, only one pin at a time may be set in a bar, the setting 01' one pin in a register-bar being effective to force any previously-set pin in said bar back to its normal position by means represented by cam-blocks not shown, interposed between the stop-pins and fully described in said oo-pending Patent No. 1,869,582, the cam-blocks, briefly explained, being displaced longitudinally of the register-bar upon depression of any pin, and by reason of their cam-formations being capable of restoring a previously-set pin as they are displaced. The 0 pin in each register-bar is normally set, and is, of course, restored by the setting of any higher pin in a register-bar.

For setting an index-pin in any register-bar, each numeral-key lever H has depending therefrom a stem 24, to rock a shaft 25, each key-lever having its own shaft. The several shafts are for actuating parallel motion pin-setting linkages 26, one for each numeral-key. Each linkage includes a pin-setting bar 21 movable edgewise and downwardly upon operation of said linkage by its numeral-key.

The pin-setting linkages are of the type shown in the aforementioned patents to Minton and Hanson. Each pin-setting bar 21 is connected at each end to a horizontal arm of a bell-crank, not shown, vertical arms of said bell-cranks being connected to the ends of an upper bar 28. Arms 29 connect the rock-shafts 25 to the upper bars 28 of their respective linkages, each shaft also having fast to its end a horizontally-extended arm 30 engageable by the numeral-key stem 24.

Index-pins are set in the register-bars as the carriage moves predetermined zones of a worksheet past the printing point. As indicated in Figure 1, downward movement of a pin-setting bar 21 is ineffective to set a pin in a register-bar unless the bar is slightly advanced to bring the pins therein under the pin-setting bars 21. This advance is accomplished seriatim for the several register-bars by the movement of the typewritercarriage 14 in presenting the aforesaid worksheet zones to the printing point. To this end, said carriage may carry tappets 3| settable along rails 32 of said carriage according to the location of zones of carriage travel in which index-pins are to be set. the typewriter-carriage M in such zone, a tappet displaces, in seriatim order, the ends 34 of jacks 35, and thereby depresses push-rods 36, to rock levers 31, each lever having one arm 38 connected to a push-rod as shown, and another arm 39 connected to one end of a transposing linkage 40, the other end of said linkage 40 pushing upon a pin 4| projecting from the side of 8. corresponding register-bar. According to the usual practice, the tappets 3| are oil'set from one another, see Figure 1, each tappet being mounted on a dog 33. By such offsetting one tappet is effective on only one set of jacks and ineffective on other sets of jacks 35, according to which set or sets of register-bars 2| shall be indexed.

With the typewriter-carriage l4 in a computing zone, a push-rod 36, corresponding to the column of the work-sheet zone which is at the printing point, will have been depressed by means of the tappet 3|, and the register-bar 2| connected thereto will be advanced, so that its index-pins 22 are under the pin-setting bars 21. Operation of a numeral-key now will cause the corresponding pin-setting bar 21 to descend and set a corresponding index-pin 22. The carriage l4 then escapes, releasing said push-rod 36 and causing the corresponding register-bar to be retracted by means of a spring-device 42. In the meanwhile, the push-rod 36 for the next column will have been depressed as the carriage took its letterfeeding step and the next register-bar will have been advanced to bring its index-pins under the pin-setting bars. In this manner is the pin-setting accomplished seriatim for the register-bars as the carriage moves a computing zone of the work-sheet, column by column, past the printing point.

The transposing linkages transpose the seriatim order, in letter-feeding direction, of pushrod operation into the proper but reverse order of the seriatim indexing of the register-bars, each linkage 4|] including a bell-crank 40* which engages the pin 4|.

The index-pins 22 are set into the path of register-bar-engaging fingers 43 formed at the upper ends of levers 44, carried by a cross-bar 45 movable forward and back for advancing the register-bars and returning the advanced bars. The purpose of said levers, which is to provide for extra carrying advance of the register-bars, and

By the step-by-step movement of the co-operating parts, will be explained further For moving the cross-bar 45 in the direction in which it is to advance and return the registerbars 2|, there are employed the usual racks 46 guided for reciprocatory endwise movement along the inner sides of side members 41 of the computing-mechanism framework. Said racks 46 carry plates 48 provided with slots 49 in which tenons 50 at the ends of said cross-bar are inserted. Said slots 48 are longer than is the width of said tenons, so that the cross-bar may slide edgewise in said slots for a purpose to be explained. By moving both racks 46 in unison, the cross-bar 45 may be moved without skewing, and, to this end, said racks are coupled by a cross-shaft 52 journaled in said framework side members 41, and having gear-sectors 53 fastened thereto, one at each end of said shaft, aligned with said racks ,46, see Figure 4. Said gear-sectors are not directly connected to the racks, but are connected thereto by intermediate pinions 54, mounted on the side members 41, to give the racks 46 the right direction of movement in respect to reciprocatory rotation of the cross-shaft 52, which may have connected thereto an operating handle (not shown), for hand operation of the computing mechanism. For operation by power, there may be used the power-drive shown in the patent to F. A. Hart, No. 1,171,403, dated February 8, 1916, said mechanism presenting a driver 55, which, driven by a crank (not shown), reciprocates forth and back in the direction of movement of the racks 46 and register-bars 2|. Con- 1 nection between said driver 55 and the racks 46 is made by meansof the usual member 56, which embraces said driver, as seen in Figure 1, and which-is fastened to the under side of the lefthand rack 46, said driver being positioned sidewise of the machine to align with said left-hand rack 46. For disengaging the power-drive, the casing from which the driver 55 projects, may be lowered in the usual manner, to thereby withdraw said driver 55 from the member 56. When the driver 55 is thus withdrawn, the computing mechanism may be hand operated by means of the aforesaid handle (not shown).

By means of the usual key-operated clutch not shown herein, but shown in said Hart patent, the driver 55 is normally disconnected from the motor-drive and is stationary in the position shown in Figure 1. By means of said clutch and its controlling key, the driver is connected to the motor-drive long enough to impart just one forthand-back movement to said driver and hence to the cross-bar 45.

When the cross-bar 45 has advanced and car- 'ried the register-bars 2| forward, to extents determined by whichever digit-pins 22 were set, in the several register-bars, there must be a suitable period of time during which certain carrying operations may take place, as will hereinafter be explained. That is, said cross-bar 45 must not immediately start its return movement after completing its advance movement, because such immediate return movement would in some cases return certain register-bars 2| before they had time to carry. To hold the cross-bar 45 stationary for a sufficiently long carrying period, the last portion of the forward stroke of the driver 55 and an initial portion of the return stroke of said driver are rendered ineffective to move the cross-bar 45, said driver 55 moving forth and back as usual, but the time-period of said portions of its strokes being apportioned to said carrying -nection 64 to said arm 62.

2,1es,uas

operations. it is to this end that said cross-bar is movable edgewise in its retaining slots 49 of the rack-plates 48, it being understood that said plates 48 will move with the drive; 55 throughout the full range of movement of said driver, and that the cross-bar 45 alone is held stationary just before and just aftersaid driver 55 completes its forward stroke. For thus holding said cross-bar 45 stationary, there may be mounted and fastened on each framework side member 41 a plate 51, in which is formed a cam-slot 58, the plates being disposed, as best seen in Figure 4, between Y the racks 46 and the walls of the side member 41. On each rack 46 there is pivoted at 59 on a suitable stud, as shown, a bell-crank lever 60, having a horizontal arm 6| for erigaging the cam-slot 58 and an upright arm 62 connected to the crossbar 45 by a link 63, the latter having a pivotal con- The horizontal arm 6| carries a roll 65 for engaging the cam-slot 58. The arms 6|, 62 of said lever are on opposite sides of the rack 46 and are joined by a cross-piece 66 (Figure 4) forming part of said lever 60. The link 63 is attached at one end to the cross-bar by screws 61,, there being provided sufficient play between the sides of the slot 49 and the tenon 50 to avoid binding between said tenon and slot as the lever 60 rocks.

The range of forth-and-back movement of the driver 55 may, as in the case herein illustrated, be just enough for full advance and return of the register-bars 2|. In such case, if the aforesaid portions of driver-movement preceding andfollowing its most advanced position are rendered inefiective to move the cross-bar 45, so that there may be afforded time for carrying, it follows that.

said cross-bar 45 must in some other manner still receive the same extent of movement as the driving member 55. To compensate for the idle portion of the forward movement of the driver 55, the cam-slot 58 is sloped downwardly at 69. This downward slope through the medium of the lever stroke, it is rendered ineffective to further ad-- vance the cross-bar 45. This is accomplished by a reverse movement of the lever 60, the cam-slot 58, to this end, including an upturned portion 10, so formed that the cross-bar 45 is held stationary because of the reverse movement imparted to the lever 60 by said upturned portion whilethe driver 55 completes its forward stroke. As the driver 55 thus completes its forward stroke, the roll 65 will have reached the position shown in full lines in Figure 11. The broken lines, indicating the roll 65 and the driver 55, indicate, with reference to the full-line positions of said roll and driver, some measure of the idle part of the stroke of said driver 55. It will be evident that at the beginning of the return stroke of said drive; 55, there is also an idle portion in which the crossbar 45 is not moved while the roll rides down the cam-slot portion 10 with consequent rotation of the lever 60. Also, in said return movement of the driver 55, the cam-slot portion at 69 will be effective to extend thereturn movement of the cross-bar 45 sufiiciently by means of said lever 60 to fully restore the register-bars 2|. cross-bar 45 in its fully returned position may abut stops 68*, Figures 4, 10 and 11.

The

is indicated in Figures 2, 15 and 16. In this latter form, the revolution of a roller 18, driven in a circle by a motor 14, is translated into reciprocatory movement of the cross-bar" by means of a link 15 fastened to said cross-bar and projecting rearwardly therefrom. The link 15 has at its rear end a head 18 forming a face Tl which the roller 18, revolving in the direction of the arrow, Figure 15, may engage to push the link I forwardly, said roller 13 in its initial position being as indicated in Figure 16. When the revolution of the roller 18 has advanced the link 15 saidciently, said roller idly passes a curved portion 18 of the face I1, said curved portion 18 being at this time concentric with a stud I8 about which said roller 18 revolves on a plate 88. The period of this idle movement of the roller 18 before it begins to retract the link 15 and cross-bar 45 is utilized to insure in this form of drive the completion of "carrying operations, already mentioned. The cross-bar 45 is, where this form of power-drive is employed, fixed in the plates, designated in Figures 2 and 15 by reference numbers 48, no movement of said cross-bar relative to said plates being required.

As seen in Figure 15, the curved portion 18 is preferably so designed that the idle movement of the roller 13 may be about evenly apportioned on either side of the extreme forward position which said roller reaches, the length of said curved portion 18 depending on the time interval to be allowed for carrying before retraction of the link 15 is commenced. Figure 15 indicates by the broken circle at the right the position of the roller 13 at that point of its revolution about the stud 18 where it commences the return of the link I5. For returning the link 15 the roller 13 reacts against a face 82 of said link. Inasmuch as the roller 13 in that part of its revolution in which it moves forward can have no effect on said face 82, the latter does not extend beyond the position from which said roller begins its forward movement. Moreover, by thus limiting the extent of the face 82, it is feasible to move the cross-bar 45 forwardly independently of 'said roller, as in hand-operation, in which case the normal position of the roller may be as indicated in Figure 16. The face 82 may for a portion of its length be concentric with the curved portion 18 of the face 11, thereby giving acceleration to the final part of the return movement of the link 15 and keeping the roller '18 in contact with the face IL-18.

The roller 13 revolves only when the registerbars 2| are to be advanced for the accumulation of a number and returned, and is, to this end, connectible to the motor 14 by a clutch (not shown) such as is shown in the aforesaid patent to F. A. Hart, which clutch with reduction gearing 83 may be enclosed in a casing 84 extending from the motor 14 and which may carry the aforesaid stud 18 around which the roller 13 revolves and which stud is spaced from the driven clutchshaft 85, for arrangement of the parts as indicated. Said shaft 85 may be connected to the roller-carrying plate 88 by a pinion 86, fast to the shaft 85, and a meshing pinion 81, fast to the plate 88. The motor 14 may be supported on a base 88 of the computing machine.

Each computing wheel 28 has fastened thereto a pinion 88. As seen in Figure 12, the pinions 88 may mesh with racks 88 formed at the forward ends of the pin-bars 2|, or, as seen in Figure 14, the pinions may be driven by said racks 88 through intermediate pinions'8l, which may be permanently in mesh with the racks 88.- As indicated in Figures 1 and 10, the computing-wheel pinions, and hence the computing wheels. are normally disengaged from both the pin-bar racks 88 and the intermediate pinions 8|. Direct engagement of the computing wheels with the racks 88 causes them to revolve clockwise during a forward movement of the pin-bars 2|. 0n the other hand, if the computing wheels be driven through the intermediate pinions 8|, during said forward movement of the pin-bars 2|, their rotation will be counter clockwise. One direction of rotation of the computing wheels may be for addition, and the opposite direction may be for subtraction. According to the arrangement of the dial-wheel numbers, as herein indicated, the clockwise rotation of the computing wheels, when directly driven by the racks 88, corresponds to addition, and the counter clockwise rotation of the wheels, when driven through the intermediate pinions 8|, corresponds to subtraction.

To shift the computing wheels 28 either downwardly for engagement with the register-bar racks 88, or rearwardly for engagement with the intermediate pinions 8|, said wheels 28, independently rotatable on a spindle 82, are retained with said spindle in a shiftable frame 88 having side plates 84 spaced apart so that the ends of said spindle 82 may be journaled therein. Said side plates 84 may be spaced apart by a crossmember 85, and by the spacing afiorded by the series of computing wheels and the hubs or collars 88 adjacent to the outer computing wheels. The computing-wheel frame 88 is held against lateral displacement between fixed plates 81, which may be secured to, and project upwardly from, a front cross-member 88 of the computing mechanism framework, said cross-member 88 serving with a rear cross-member 88 to space apart the aforesaid side members 41 of said framework.

For supporting the computing-wheel frame 88 between said fixed plates 81, so that it may be shifted-there may be used a cross-rod |88 supported by and spanning said plates 81. Slots |8| at the rear end portions of the computing-wheelframe plates 84 embrace said cross-rod, and when the computing-wheel frame is in normal position, in which the computing wheels 28 are disengaged, said slots |8| extend in a horizontal direction. The forward portion of the computing-wheel frame may be supported on arms I82 projecting from a rock-shaft I88, each computing-wheel frame being provided with one of said arms, as shown in Figure 4. Each arm I82 has a slot I84 which, when the frame 88 is in normal position and the computing wheels are disengaged, extends in a horizontal direction. Said slot I84 embraces the cross-member 85 of the computing-wheel frame.

From Figure 1 it will be seen that the slots IN and I84 guide the frame for rearward and forward shifting, the rearward shifting being effective to engage the computing wheels with the intermediate pinions 8| the forward shifting of said frame conversely disengaging the computing wheels from said intermediate pinions 8|. Figure 14 indicates the computing wheels engaged with said intermediate pinions. 1

From Figures 1 and 11 it will also be seen that the frame 88 may turn about the cross-rod |88 as a fulcrum, such turning being effected by rocking the shaft I88. In this case the computing wheels 28 will be directly engaged with the pin-bar racks 88, as indicated in Figures 11, 12 and 13.

Preparatory to the forward movement of the I register-bars 2|, the computing wheels are brought into engagement with either the register-bar racks 90 or the intermediate pinions 9|, and similarly, preparatory to the return movement of the register-bars, the computing wheels are. disengaged again so as not to be reversed by the return movement of said register-bars.

' Selective connections (not shown), for coupling the driving mechanism of the computing machine to the rock-shaft I03 or to a link I06, may be provided for effecting shifting of the computing-wheel frames 93 at the proper times during. a computing-machine cycle. The rock-shaft I03 may be split into individual rock-shafts, one for each of the registers, to control the registers independently, or there may be one rock-shaft common to all the registers, and it will be understood that said selective connections may be made accordingly. Such selective connections predetermine whether the computing-wheel pinions 89 are to be presented directly to the racks 90 as for addition, or whether they are to be presented to the intermediate pinions 9| as for subtraction. The

fixed plates 91 may have two-ways slots I01, into which the computing-wheel spindles 92 may extend, so that their ends may receive screws 91, whose heads bearing against the outer surfaces of said plates 91 serve to retain said spindles endwise. Horizontal and vertical branches of said two-way slots I01 serve to hold the frames 93 against displacement transversely of said branches.

As already stated, the levers 44 on the general-operator cross-bar have register-bar-engaging fingers 43 for pushing the register-bars forward. How said lev'ers 44 and their register-bar-engaging fingers operate to advance the register-bars 2I extra unit-spaces for carrying, will now be explained. Said levers 44, of which there is one for every register-bar, may be mounted on a common fulcrum-rod I08, and there may be one such fulcrum-rod for every set of register-bars of the computing mechanism retained between ears I09 of a bracket IIO secured to the cross-bar 45, said ears projecting downwardly and forwardly from said cross-bar. The levers 44, individually rockable on their fulcrum-rods, are spaced apart and located, as by collars orv hubs III, Figure 4. The register-bar engaging fingers 43 of said levers 44 are aligned with the pins 22 of their respective registerbars, and may be formed by tabs bent at right angles to said levers.

The carrying of a tens value from one computing wheel to a wheel of next higher denomination is, according to the present invention, ef-

fected by advancing the register-bar for said higher wheel an extra unit-space, the extra advance being effected by causing the lever 44 to be rocked counterclockwise from the position seen in Figure 12 to the position seen in Figure 11, 13 or 14. As seen in Figures 1% and 12, a register-bar-engaging finger 43, backed by the cross-bar 45, may advance a register-bar by engaging a depressed pin 22. The advance of the cross-bar 45 and hence of the fingers 43 thereon, when abutting the forward side of said crossbar, is always to the same extent, and the extent of advance of a register-bar therefore depends upon which index-pin is depressed.' If the 0 pin, which is the first pin from the front of the machine, is not displaced from its normally-depressed position by the setting of a higher pin, the register-bar will not be advanced, because the position which'the cross-bar, with the corresponding finger 43 bearing thereagainst, reaches at the end of its advance movement is such that said finger 42 just touches the depressed 0" pin. If a 1 pin is depressed, the register-bar will be advanced until said 1 pin is in the position from which the "0 pin moved in such' advance of the register-bar. Similarly, by depression of a higher pin, the register-bar will be advanced until said higher pin is in the position which the ,0 pin left in said advance.

Thus, it will be seen that, irrespective of the value of the depressed pin 22, the depressed pin always reaches the same position, and'that it is therefore feasible to provide stops which will prevent overthrow of the register-bars as they reach the ends of their respective advance movements, and that said stops will be efiective for any. extent of said advance movements as determined by the values of the depressed pins 22. A stop I I2 for each register-bar is therefore provided and is caused to abut the forward side of the depressed pin as a register-bar carrying said pin reaches the end of its advance position.

Two conditions govern the application of. the stops II2, one condition being that said stops must be individually shiftable to permit an extra carrying advance of their respective registerbars, the other condition being that said stops, when the computing mechanism is in its normal condition, that is to say, when the registerbars are not being advanced to accumulate a number, must be sufficiently removed from the normally depressed 0 pins to permit the aforesaid slight advance of theregister-bars seriatim during the indexing of the register-bars.

To these ends, the register-bar stops II2 may be formed on the rear ends of elongate bars I II, which are to be shiftable simultaneously from a normal position, indicated in Figure l, wherein the stops II2 are far enough removed from the depressed 0 pins, as seen in Figure .l, to

permit the aforesaid seriatim advance of the register-bars, to the position indicated in Figure 12, and more clearly indicated in Figure 10 by the dot-and-dash outline of a stop H2, in which latter position the stops II2 may abut the depressed pins of the advanced registerbars or the 0 pins of the register-bars that are not advanced. From said latter position, the bars H3, and hence the stops II 2, are to be individually movable in a forward direction to permit an extra carrying advance of the corresponding register-bars, the forward carrying movement of the bars II3 being limited, however, so that the stops II2 are also effective to prevent overthrow of the register-bars when said registerbars carry. The forward carrying movement of any bar H3 is also utilized to effect, as will be explained, a carrying displacement of the corresponding lever 44 and its register-bar-engaging finger 43.

To these ends, the bars II3 are urged forward,

by individual springs II4, but are normally latched in non-carrying positions over a transverse latch-bar H5, each bar 3 having a latching edge IIG, which normally abuts the rearward edge of said bar H5. The several bars H3 are pivotally connected 'at their rearward ends to upstanding arms III of levers II8 of the first order individually rockable on a fixed fulcrum-rod I I9. Arms I20 of said levers H8 extend, in the normal positions of said levers as seen in Figure 1, downwardly and rearwardly. To effect rearward movement of all the bars II3 to bring the stops 2 from the positions seen in Figure 1 to the position seen in Figure 10 or 12, in which latter position the stops are effective to prevent overthrow of the register-bars, the latch-bar H5, together with all the bars H3 latched thereover, is advanced rearwardly during the advance movement of the cross-bar 45 as will later on be explained. As the bars H3 are so moved simultaneously, their levers H8, mounted on the fixed fulcrum-rod H3, are rotated clockwise, so that the arms I28 of said levers H8 are shifted from the position indicated in Figure 1 to the position indicated in Figure 12. Said latter position of the arms I28 is such that pins I2I therein just abut downwardly-extending arms I 22 of the corresponding levers 44 on the cross-bar 45 when the corresponding register-bars register a non-carrying advance, as indicated in Figure 12. From Figure 12 it will be seen that, with the arm I22 abutting the pin I2I and the register-bar-engaging finger 43 abutting the cross-bar 45, and the bar I I 3 latched over the bar I I5, a register-bar whose depressed pin 22 is closely confined between the stop I I2 and finger 43 is secured not only against overthrow, but is also secured against rebound.

Referring to Figures 10 and 11, it will be further seen that upward displacement of the forward end of one of the bars H3 will cause said bar to move forwardly under the pull of the spring H4.

As a bar H3 thus released from the latch-bar H5 moves forwardly, it rocks its lever H8 counterclockwise to the position seen in Figures 11, 13 and 14, and which position may be determined, as by abutment of the lever I I8 against a transverse rod I23 supported by and spanning the fixed plates 91 of each register. It will be evident that a lever H8, thus rocked counterclockwise by release of its bar H3, will also cause the corresponding lever 44 on the cross-bar 45 to be rocked counterclockwise, thereby causing the register-bar-engaging finger 43 on said lever 44, and hence the corresponding register-bar itself, to be advanced in respect to said cross-bar 45. Thus each register-bar may receive an extra movement depending upon the release of a bar H3. To prevent the levers 44 from falling into a disabling position when not engaging an indexpin 22, as, for example, when the cross-bar 45 is fully returned, each lever 44 may have an arm I 24 to limit its counterclockwise movement, as is indicated, Figure 11, by the abutment of said arm with the bracket Hll attached to said crossbar 45.

The release of a bar H3, as aforesaid, is to be effected every time a computing wheel, of next lower order to the register-bar controlled by said bar H3, passes its carrying point, and each computing wheel has therefore, projecting from its periphery, a carrying tooth I25. On account of the different positions of the computing wheels in addition and subtraction, the carrying teeth I25 of the several wheels operate to release the bars I I3, preferably through intermediate carrying levers I26 individually rockable on a fulcrumrod I21 supported between the side plates 94 of the computing-wheel shift-frame 83, and spaced and located on said rod I21. as by collars or hubs I28, Figure 11. Each carrying lever I26 has a cam-shaped arm I29 arranged so that said carrying lever may be rocked by the carrying tooth I 25 in either direction of rotation of the computing wheel. As a carrying lever I26 is rocked, the end of an arm I38 thereof moves upwardly against and displaces the forward end of a corresponding bar H3, and thus releases said bar H3 from the latch-bar I I6.

The location of the ends of the arms I38 of the levers I26 is so arranged with respect to the cross-rod I68 that said ends of the arms I38 describe an are or line when the computing-wheel shift-frame 93 is swung around said cross-rod I00 for engaging the computing wheels directly with the register-bar racks 88, which is substantially the same as the line along which said ends of the arms "I38 move as the computing wheels are shifted rearwardly with said frame 83 for engagement with the intermediate pinions. Thus the carrying levers I26 'are effective in either adding or subtracting position of the computing wheels 20, to release their respective bars H3.

A carrying train from any computing wheel to the register-bar of the computing wheel of next higher denomination includes the carrying lever I26 v actuated by the former computing wheel, the bar-H 3, releasable by said carrying lever I26, the lever H8, connected to the rear end of said bar H3, and the lever 44, controlled by the latter lever H8, the register-bar engaging finger 43 of said lever 44 being aligned with the pins 22 of the register-bar of the computing wheel of said next higher denomination. Thus, one end of said train is the arm I29 of the carrying lever I26, and is adjacent the computing wheel of lower denomination, and the other end of said train is the register-bar-engaging finger 43 for the register-bar of next higher denomination. The required offset of said ends of the train may be effected by forming and arranging the parts thereof as indicated in Figures 4 and 5. As indicated in Figure 5, the carrying lever I26 may be within the plane of rotation of the carrying tooth I25. The forward portion of the bar I I3 is aligned with said lever I26, the rear portion of said bar being offset to the left by bends I32 and having the stop H2 formed by a tab bent to the left to align with the pins 22 of the regis-v ter-bar of next higher denomination. The lever H8 is pivoted on the left side of said bar H3 and its pin I2I projects to the left to align with the arm I22 of the lever 44 for said register-bar. said lever 44 has its finger 43 in the form of a tab bent as shown to align with said pins 22 of said register-bar.

Each bar I I3 is connected to its lever H8 by a headed pivot-stud I33. The levers H8, individually rockable on their fulcrum-rod H8, may be spaced and located on said rod as by hubs or collars I34, each register having one of said rods which is supported by and spans the fixed plates 91. Although the units register-bar never carries, it is nevertheless provided with a bar H3, a lever H8 and a lever 44, the latter having its register-bar-engaging finger 43, inasmuch as these parts also prevent overthrow and rebound of the units register-bar. No carrying train extends from the computing wheel of highest denomination, which is the first wheel from the left of the register.

In most cases, the levers 44 are rocked positively by the positively-driven movement of the cross-bar 45 itself when carrying is to be effected and therefore an extra carrying advance of a register-bar is effected positively. That is to say, in most cases carrying bars H3 will have been released, and the levers H8, connected thereto, will have been rocked before the crossbar 45, with its register-bar-engaging levers 44, effects contact of the arms I22 of said latter levers with the pins I2I of the arms I20 of levers II8. Thus, said arms I20 and their pins I2I forminterponents which, by the release of their respective bars H3, are thrust into the path of the advancing cross-bar levers 44 on the crossbar 45. It will be seen, therefore, that as the arms I22 of the cross-bar levers encounter the pins I2I, thus thrust into said path, the crossbar levers 44 will be caused to rotate counterclockwise to an extent equivalent to advancing their register-bars an extra unit-space, and which extent, it will be understood, may be determined by suitable proportioning and arrangement of the parts as illustrated in the drawings. In those cases where a carrying advance of a register-bar is effected, after said register-bar has reached its advanced position, as indicated in Figure 12, the necessary carrying displacement of the parts involved is efiected by the power afforded by the spring H4.

The lever I I8, whose arm I is thus thrust into the path of the advancing cross-bar lever 44, is to be stabilized against counter-rotation while it co-operates to rock said cross-bar lever 44, and the latter lever 44 is also to be locked against counter-rotation after it has been rocked to the position of Figure l1, 13 or 14. To this end the arm I22 of the lever 44 has an edge I36 extending in such direction relatively to the fulcrum of the lever H8, and clearly indicated in Figure 12,

that said lever I I8, if it is caused to be rocked by unlatching of the bar H3, may correspondingly rock the cross-bar lever 44. At the endof this rotation of the two levers 44, H8, the pin I2I I of lever IIB arrives opposite a scooped-out portion I3'I of said edge I36. A point or hump I38, at the intersection of the edge I36 and its scooped-out portion I31, affords such point of contact with the pin I2I as the lever 44 reaches said pin after the latter has already been thrust out, as aforesaid, that the lever 44 is rocked spaced and located on said rod I2'I as by collars pleting its advance movement.

As indicated in Figure 11, said point or hump I38 approaches and makes contact with the pin "I on the dot-and-dash line I39. In the ensuing rocking of the lever 44 to the position shown in Figure 11, 13 or 14, as the point or hump I38 is thus arrested while the cross-bar completes its advance, it will be seen that the line of reaction afiorded by the lever H8 is to be substantially through or on a favorable side of the fulcrumcenter of said lever, and hence there is substantially no tendency to rock said lever contrariwise, and therefore there is substantially no tendency to relatch the bar II3. As the lever thus, in the latter case, is rocked to the position shown in Figure 11, the scooped-out portion I31 settles against the pin I2 I. Since said portion I31 may, at its final point of contact with the pin I2I, be substantially perpendicular to the aforesaid line of reaction through the fulcrum-center of the lever II8, as is clearly indicated in Figure 11, the lever 44 is also secured against counter-rotation after it reaches said position, and hence there is no tendency to rebound of the register-bar, even when said bar receives an extra advance for carrying.

The stop-bars II3 are spaced laterally and guided at their forward ends by a slotted transverse bar I40, which may also have slots MI, in which the front portions of the register bars 2I are guided. The stop-bars II3 are notched at their front ends to form an upper branch II3 which is received by a slot in said transverse bar I40 and,a lower branch II3 which underlies said transverse bar to limit the upward movement of the forward end of a stop-bar II3. Said register-bars may be guided at their rear portions in slot-ted transverse plates I42, secured to the cross-member 99 of the framework. Said transverse bar I40 may be retained between the fixed plates 91, which retain the computing-wheel frame 93 against lateral displacement. Each pair ofvsaid fixed plates may have rearward extensions I43, between the ends of which may be retained the fixed fulcrum-rod H9 and abutmentrods I23 of the levers II8.

Each of a pair of saidfixed plates 91 may have a slot I44, the opposite slots of the pair of plates serving to retain the latch-bar II5 whose ends may be guided in said slots, as indicated in Figures 5 and 8. The shifting of said bar back and forth in said slots I44 is effective not only to bring the register-bar stops II2 into and out of their stopping positions, as aforesaid, but the forward shifting of said latch-bar H5 is also effective to cause the relatching of those stop-bars I I3 which have been released. With the position of the parts as seen in Figure 11, 13 or 14 in which the released bars II3 are held by abutment of their levers II8 against the rod I23, it will be evident that shifting of the latch-bar II5 forward, that is, toward the left, to the position in-' dicated in Figure 1 or 10, is effective to relatch the released bars.

All of the latch-bars II5 of the several registers are thus shifted back and forth simultaneously, and, to this end, are connected to a universal bar I41, which extends across the machine to span the several registers, as shown in Figures 4 and 5, the ends of said bar I41 slightly overlapping the outer side plates 91 of the first and last registers. Movement of the universal bar I41 back and forth is transmitted from the cross-shaft 52,

' which, as previously explained, has a reciprocain a slot I5I, cut in a post I52 upstanding from the cross-member 98 of the framework and secured to said cross-member by a screw I54, Figure 3. The sides of the slot I5I retain the forward end of the slide I48 laterally, while the block I50 co-operating with the slot I49 in said slide retains the forward end of said slide vertically. The rear end of the slide I48 has a slot I53 which slidably fits a rectangular block I55, which is provided with a hole for a running fit on the cross-shaft 52.

For enabling the cross-shaft 52 to reciprocate the slides I48, there is fastened to said shaft two cams I56, one cam being adjacent-each slide I48. There is secured to each slide I48 a closure-plate I51, having a slot I58. Said closure-plate is secured to its slide I48, by screws I59, on the side opposite to which the cam I56 is disposed. There are on each slide I48 a front cam-roll I60 and a rear cam-roll mounted on said slide on a headed stud I62, and the latter roll I6I being mounted on the closureplate I 51 by a headed stud I63.

The front roll I60 has an outer flange I64, which may bear against the side of the cam I56 to co-operate with the closure-plate I5'I in re- I6I, the former being directly taining the slide laterally. For such lateral retention of the slide, the top and bottom edges of the slot I58 of the closure-plate overlap the top and bottom edges of the slot I53 in the slide I48, so that said closure-plate bears on the side of the block I55 which in turn bears on one side of the cam I58 which thus retains said slide laterally, the roll-flange I64 bearing on the other side of said cam,

For coupling the slide I48 with the universal bar I41, each slide I48 may have a notch I85, which includes at its forward side a tongue I66, which may overlap and underlie the forward edge of the universal bar, and thereby serve to retain the latter at said forward edge. For easy assembling of the parts, the rearward side I65 of the notch IE5 is spaced from the rearward edge of the universal bar, the latter being secured at said rearward edge, however, by means of a block I61 formed as best seen in Figures 3 and 5, said block including a forwardly-projecting tongue I68 which overlaps and underlies the rearward edge of said universal bar. The block I61 is slotted at I 89 to embrace the sides of the slide I48, and close the gap between the rearward side I85 of the notch 585 and the universal bar I41, said block being secured in place by a screw I10.

Connection is made between each latch-bar I i5 and the universal bar I41 by means of a pair cf links I1I engaging the latch-bar II5 near its ends, and being disposed, therefore, adjacent the fixed plates 91 which support said latch-bar at its ends, as aforesaid, by means of the' slots I45. Each latch-bar II5 may, as best seen in Figure 7, have at each end a notch I12 to form with a notch I13 in the link I'II an interlocking joint connecting said latch-bar H5 and link I1I. The rearward end of each link has a slot I14 which slidably fits a stud I15 projecting from the inner side of the adjacent fixed plate 91. Thus, by means of said slots I14, studs I15 and the slots I44, the latch-bar II5 and its pair of links I1I are guided for back-and-forth movement and are wholly supported by the register fixed plates 91. For connection with the universal bar I41, each link I1I has a notch I16, Figure 7, the front and rear sides of which may, as seen in Figure 5, embrace said universal bar. Each latch-bar may also carry an anchor-plate I11, having perforations for attaching the ends of the springs II4 that pull the stop-bars II3 forward as they are unlatched. In order that the pull of said springs II4 may have a downward component, the anchor-plate I11 is somewhat below the spring-ends attached to said stop-bars II3, said downward component of the spring-pull serving to pull the forward end of the stop-bar down when the latchbar I I5 is moved forwardly, and thereby causing the stop-bar to become relatched. For thus positioning the anchor-plate I11, it is spaced from the latch-bar II5 by collars I18, and is secured by screws I19.

Means to ensure positive relatching of the stopbars H3, and designed to supplement the downward pull of the springs II4, include, for each register and the set of stop-bars II3 therein, a swingable bail I80, having side arms I8I, whereby said bail may be pivoted to the inner sides of a pair of fixed plates 91, by pivot-screws I82, threaded into said fixed plates. Said bail I80, extending transversely of the several register-bars 2I and stop-bars H3 of the register, is provided with slots I83, to clear said register-bars and afford prongs, the lower ends of which, reaching downwardly between the register-bars, may engage and push against the top edges of the stopbars H8. It will be seen that if said bail I is pressed downwardly after the latch-bar II5 has been moved forwardly for relatching the stopbars II3, each stop-bar will be positively urged down, to ensure that the latching edge I I6 of each stop-bar I I3 will be properly caught by said latching bar II5. For imparting such downward movement to the bail I80, the right arm I 8| of each bail is extended rearwardly to include a lug I84, which may be engaged by suitable means to effect the depression of said bail I 80. Such means may be formed on a cross-shaft I85, in the form of teeth I95, which, in a revolution of said shaft, pass over and displace said lug I84, with a consequent depression of the bail I80. Said teeth may be separately inserted in thev cross-shaft I85, there being one tooth for each register, each tooth having a step I88, which is received by a transverse hole in the shaft I85, and is secured by a nut I 89, which may be countersunk below the surface of said shaft. The shaft I receives a complete revolution during a computing-machine cycle to fulfill operation of means (not shown) for. controlling other operations of the computing mechanism,saidcompleterevolution being derived from the reciprocatory motions of the cross-shaft 52 and left-hand rack 46.

To this end, the cross-shaft is provided an additional sector I90, whicimay engage a sector I9I loose on the shaft I85. Another sector I92, also loose on said shaft, is coupled to the left rack 46 by an intermediate gear I93, Figure 4. A clutch-device I94, disposed between the sectors I9I and I92, is keyed to the shaft I85 and is arranged to receive from the opposite rotations of said sectors I9I and I92 one continuous rotation asthecross-shaft 52 and rack 46 are reciprocated once in a computing-machine cycle. Details of the construction of said clutch-device I94 and its operation with respect to the sectors I9I and I92 are fully set forth in my original application,SerialNo.324,353 (nowPatent No. 1,927,951, dated September 26, 1933). The sector I9I is retained by a collar 202, fastened to the crossshaft I85, the latter being journaled in the side members 41 of the framework. Inasmuch as the bail I80 is depressed when the latch-bar H5 is in its forward position, restoration of said bail may be effected by the rearward movement of said latch-bar II5. To this end, the left arm [M of said bail has a downward and rearward extension 203, whose lower end, see Figure 10, is in the path of the latch-bar H5 when said latch-bar is to be moved rearwardly. Rearward movement of said latch-bar II5 will therefore cause upward displacement of the bail I80 as seen in Figure 11. While the latch-bar H5 is in said rearward position, the bail I80 is held up and so cannot interfere with upward movement of the stop-bars II3, such upward movement taking place whenever a carrying lever I28 is operated.

The cross-shafts 52 and I85 and the generaloperator cross-bar 45 may be supported at their middle portions by a transverse bar I96, secured to and fastened to the front and rear cross-members 98, 99 of the framework. The general-operator cross-bar 45 may bear directly upon the top of said transverse bar I98. To enable said bar I96 to support the cross-shafts 52 and I85, each of the latter is provided with a grooved collar I 91, which may have a running fit on its shaft, and one flange of which may bear upon the upper edge of an angle-piece I98, secured to and extending upwardly from the transverse bar I96. The

grooves of said collars I91 receive slots I99 formed in a plate I99, which is attached to the upstanding side of the angle-piece I98 by screws 200. The plate I99 and grooved collar I91 constitute middle bearings for the shafts 52, I85, which may be easily dismantled or reassembled to facilitate removal or installation of either shaft '52 or I85. It will further be noted that the arrangement of the slides I48 and of the mounting and operating means therefor is also conducive to easy assembly and disassembling of the parts. Furthermore, any register may be easily removed when the screws 2!, which secure it to the cross-member 98, Figure 10, are removed. The bar I41 may be retained against endwise displacement by two pins I41 projecting upwardly therefrom and abutting the sides of the transverse bar I96.

The contours of the cams I56 may be so arranged that the latch-bars H5 and the bars H3, the latter having the register-bar stops II2, are shifted forwardly gradually, but soon enough to bring the stops II2 into effective position before a register-bar reaches the end of its advance movement, and similarly the return of the latchbar I I5 is also effected gradually through said arrangement of the contours of the cams I56, the return of the latch-bar H5, and consequently of the bars H3, not commencing, however, any sooner than say, the time at which the returning cross-bar 45 picks up the farthermost advanced register-bar.

Alignment and location of the teeth of the computing-wheel pinions 89 may be secured by individual spring-pressed detents 294, which fit the tooth-spaces of said computing-wheel pinions 89. Said detents 204 may be swingably mounted and spaced on the shaft or cross-mem ber 95 and their springs 2II4 may be light enough in comparison with the springs H4 so as not to unduly impede the carrying force of said latter springs. i

As an illustration of the operation of the computing mechanism, consider the following computing example, in addition:

The operator first sees that the computing mechanism is conditioned for addition. The tappet 3I and a tabulating stop 205 having been properly set in relation -to the work-sheet zone in which the first item 22 is to be typed, the operator presses the appropriate denominational tabulating key (notshown), and thereby, through connections not shown, raises the corresponding denominational stop 206 to set thetypewritercarriage I4 at the tens column of said zone.

The item 22 is then typed on the work-sheet by operation of the numeral-keys I0, and during this operation the 2 index-pins 22 are caused to be set in the tens and units register-bars 2| of whatever register the tappet 3i is set for, it being understood that if only one tappet 3I is set only one set of register-bars will be indexed, and that by setting two tappets 3|, one for one register and one for another, accumulation may be effected in two registers. The indexing of the 2" pins in the tens and units registering-bars caused the 0 pins of said bars to be displaced upwardly, by means not shown but described in my aforesaid co-pending Patent No. 1,869,582.

The number 22 having thus been typed on the work-sheet and corresponding index-pins hafig been set, the computing mechanism is now ready to be operated for the accumulation of said number in the computing wheels. To this end, the clutch-device of the power-drive is caused to be engaged by retraction of the usual clutch-trip pin, which may be operated by a suitable key and connections, said clutch-device, trip-pin, key, and connections being of the type shown in the aforesaid patent to Hart. Said clutch-device is of such character that the computing-mechanism driver 55 makes one complete forth-and-back movement and no more, inasmuch as said clutchdevice in the normal operation thereof automatically disengages itself at the end of said movement, and the cross-bar 45 therefore makes only one complete forth-and-back movement. Similarly, if the power-drive shown in Figures 2, 15 and 16 be employed, the roller I3 of said drive makes only one revolution and no more, starting from and ending in the position shown in Figure 16.

In the initial portion of the forward stroke of I the cross-bar 45, the computing-wheel pinions 89 are caused, by the rocking of the shaft I93, to drop into direct engagement with the register bar racks 90. As the cross-bar 45 proceeds further in its advance stroke the tens and units register-bar-engaging fingers 43 on said cross-bar engage the depressed 2 index-pins of the tens and units register-bars which are thereupon advanced two unit-spaces and the tens and units computing wheels 20 are also rotated clockwise two unit-spaces. Before the rack-engaging fingers 43 engaged the depressed 2 pins, the reg ister-bar stops I I2 on bars I I3 were caused, by the rearward movement of the latch-bar H5, effected by its operating connections, to be moved rearwardly to the position indicated in Figure 9 or 12, and in which position said stops abut the depressed 2 pins of the fully-advanced registerbars. At the end of the advance of said registerbars, the relative positions of the register-bar stops II2, the register-bar-engagingfingers 43, and the cross-bar 45 in respect to the depressed 2 index-pins, are as indicated in Figure 12, from which it will be seen the advanced registerbars are secured against overthrow and rebound.

The cross-bar 45 having now fully advanced the tens and units" register-bars for accumulation of the number 22, said cross-bar is caused, through the effect of the cam-slot portion I9, Figure 11, or the curved portion I8, Figure 15,

to be stationary for an interval of time, this stationary period in the operation of the cross-bar 45 affording time for carrying. No carrying operation, however, takes place during the accumulation of the number 22, it being understood that all the register-wheels were originally set at 0. The cross-bar 45 only commences its return after the roll 65 has reached, in the return movement of racks 46, the bottom of said cam-slot portion Ill. drive shown in Figure 15, after passing the curved portion I8 of the cross-bar links I5 the continued revolution of the driving roller I3 causes the cross-bar 45 to be returned.

In the initial portion of the return stroke of the cross-bar 45, the computing wheels are caused, by reverse rocking of the shaft I03, to be disengaged from the register-bar racks 90 so as not to be reversed when the cross-bar 45 picks up the register-bars. The cross-bar 45 in its return movement picks up the advanced registerbars by engaging the projections I thereof, and,

Similarly, in the powerwith the co-operation of the spring-device 42, returns them fully to their normal positions, as seen in Figure 1. The cross-bar l5 itself does not move back far enough to effect the full return of the register-bars. Said spring-device 42 completes the return of said register-bars inorder to leave a gap I81 (Figure 10) which affords sufficient room for the seriatim advance of the register-bars for indexing of the pins 22. During the return stroke of the cross-bar 45 and its operating train, including the cross-shaft 52, the register-bar-stops II2 on bars II3 are moved forwardly again by the advance of the latch-bar I I5 effected through its described operating connections with said shaft 52 to leave room between the pins and said stops 'for the aforesaid seriatim advance of the register-bars for pinsetting.

Near the end of the cross-bar 45 return movement, pin-restoring bails not shown, but described in my original application No. 324,353, are operated to effect restoration of the 2" pins of the tens" and units register-bars by resetting the 0" pins of said register-bars.

After an accumulating cycle of the mechanism for the item "22 is thus completed, the typewriter-carriage ll being returned either before or after said cycle and the platen line-spaced, the next number 8 is typed on the work-sheet after tabulating said carriage ll to the units column. The 8 pin will thereby be set in the units register-bar with a corresponding restoration of the 0 pin of said register-bar, and the clutch-' device of the power-drive is tripped to again operate the mechanism to accumulate 8. During this accumulating operation, the units register-bar advances eight spaces, thereby revolving the units computing wheel also eight spaces clockwise, and causing it to pass the carrying point, inasmuch as it previously registered 2 and now registers 0". As the units wheel so passes the carrying point, its carrying tooth I25 rocks the units" carrying lever I26 and releases the corresponding stop-bar II3 to effect a forward advance of the register-bar-engaging finger 43 for the tens register-bar which is thus advanced one unit-space. The tens" wheel therefore, instead of showing 2", now shows 3. In this particular example, the carrying tooth I25 of the units wheel released the stop-bar II3 as the units register-bar was moving through its last unit-space of movement, so that the carrying advance of the tens register-bar is probably effected by the power of the spring Ill of the,

released stop-bar I I 3, the actual carrying advance of the "tens register-bar probably taking place while the cross-bar 45 is in its stationary period.

During the return stroke of the cross-bar 45 and the accompanying counterclockwise rotation of the cross-shaft 52, all the stop-bars II3, except the one which was released for carrying and whose lever III therefore already abuts the rod I23, are moved forwardly again by the forward movement of the latch-bar II5, connected to said cross-shaft 52, said latch-bar passing slightly beyond the latching edge -I I6 of the released stop-bar, and thereby causing the released stop-bar to be latched again, as indicated in Figure 1. Similarly the latch-bar I I also passes,

it may be noted, slightly beyond the latching edges IIB of the other bars II3, after the levers II8 of said other bars in their forward movement finally abut said rod I23. In the relatching of the bars II; the bails IlII co-operate with the springs Ill in forcing the bars downward,

so that the latching edges II are sure to be caught by the latch-bar I II when the latter moves rearwardly in a succeeding'cycle. As best seen in Figure 10, the balls III are down when the machine is at rest in its normal position, the

several bail-actuating teeth I being then over the lugs I84 of their respective bails. This locks the carrying bars H3 against accidental unlatching while the machine is at rest. Aside from the release and ,restorat ion of a stop-bar III and its related parts for carrying, the operations of the mechanism are the same for the accumulation of "8" as were the operations for the accumulation of "22.

In the subtractive computing example of the units register-bar is set, it being noted that the pin which is set always has the same value as the operated numeral-key, irrespective of whether the item is to be added or subtracted. It may also be noted that in subtraction the zero-pin of a register-bar is also, as in addition, restored by the setting of a higher pin in said bar.

In the accumulating operation of the computing mechanism which is now to take place, the computing wheels must be rotated reversely or counterclockwise in order that the 1 may be subtracted. Before a computing cycle is initiated therefore by engagement of the clutch-device of the power-drive, a subtraction-key (not shown) must be first pressed in. By presing in the subtraction-key, mechanism not shown, but of the type shown in my original application No. 324,353,

is conditioned so as to be effective during the computing-machine cycle to shift the computing-wheel frame 83 rearwardly before the register-bars advance, and then forwardly again before the register-bars return, such'rearward and forward shifting of said frame 93 causing the computing wheels to engage the intermediate pinions 9| before the registerbars advance and to be disengaged before said register-bars are returned. The rock-shaft Ill remains stationary during the subtractive accumulating operation.

With the computing wheels 2| moved rearwardly into engagement with the intermediate pinions 9i, the forward movement of any pinbar 2i causes its computing wheel to be rotated counterclockwise. The units wheel which registers 0 is therefore rotated one space counterclockwise from said 0" position to the 9" position, and thus the carrying tooth I of said "units wheel displaces its carrying lever I26, causing the corresponding bar 3, which extends to the tens" register-bar to be released, with the result that said tens" egister-bar advances one unit-step forwardly. Thereby the tens wheel, driven through its intermediate pinion 9|, is rotated counterclockwise one step or from "1 which it previously registered to 0", and the computing wheels as a whole now indicate 9, whichis the correct result of the above subtractive computing example.

Exceptfor the reversed rotation of the computing wheels caused by their engagement and disengagement with the intermediate pinions 8| instead of with the register-bar racks 90, the accumulating operation of the mechanism and the preparatory indexing of the pins 22 are the same for subtracting a number as for adding a'numher, that is to say, the operation of the carrying trains as the same in both cases, and the restoration of the index-pins, by resetting all pins, is also the samein both cases.

At the end of a subtractive computation the mechanism may be restored to its normal additive condition by releasing the subtraction-key, whereupon the mechanism, mentioned as aforesaid as being disclosed in my original application No. 324,353, is conditioned to rock the shaft I03 during an additive computing-machine cycle. Variations may be resorted to within the scope of the invention, and portions of the improvements may be used without others.

Having thus described my invention, I claim:

1. In a computing machine; a reciproeatory] register bar having a normally set zero pin and a normally unset higher pin, said zero pin being restorable concomitantly with the setting of the higher pin, said register bar being slightly advanceable from a normal position preparatory to efiecting pin setting, a reciproeatory general operator for engaging the set higher pin and advancing said register bar, during a cycle of said general operator, after the pin-setting operation, said register bar being restored to normal position at the end of the cycle, a stop for confronting the set pin to counteract undue advance of the register bar by the general operator in said cycle, said stop being normally retracted from an effective position to permit the slight advance of the register bar for pin setting, said stop in its efiective position confronting the zero pin when said register bar is in normal position, and means cooperative with said general operator to place automatically said stopin efiective position during said cycle.

2. In a computing machine; a reciproeatory register bar having a normally set zero pin and a normaly unset higher pin, said zero pin being restorable concomitantly with the setting of the higher pin, said register bar being slightly advanceable from a normal position preparatory to eifecting pin setting, a reciproeatory general operator for engaging the set higher pin and advancing said register bar, during a cycle of said general operator, after the pin-setting operation, said register bar being restored to normal position at the end of the cycle, a stop for confronting the set pin to counteract undue advance of the register bar by the general operator in said cycle, said stop being normally retracted from an effective position to permit the slight advance of the register bar for pin setting, said stop in its effective position confronting the zero pin when said register bar is in normal position,- and means cooperative with said general operator to place automatically said stop in efiective posi-- tion during said cycle, said means including a timing device operative to place said stop in effective position before the register bar reaches the end of its advance by the general operator and to restore said stop to retracted position before the end of the cycle.

HENRY L. PITMAN. 

